Phase transition close to room temperature in BiFeO3 thin films

TL;DR

This study demonstrates a reversible phase transition near room temperature in strained BiFeO3 thin films, identified through Raman spectroscopy, highlighting potential for temperature-sensitive applications.

Contribution

It reveals a temperature-induced phase transition in supertetragonal BiFeO3 films stabilized by substrate strain, a novel finding in multiferroic oxide research.

Findings

Reversible phase transition at ~100°C in T-BFO films

Strain stabilizes supertetragonal phase near room temperature

Raman spectroscopy confirms phase change

Abstract

BiFeO3 (BFO) multiferroic oxide has a complex phase diagram that can be mapped by appropriately substrate-induced strain in epitaxial films. By using Raman spectroscopy, we conclusively show that films of the so-called supertetragonal T-BFO phase, stabilized under compressive strain, displays a reversible temperature-induced phase transition at about 100\circ, thus close to room temperature.